To test the road safety of (motor) vehicles, it is known to simulate traffic accidents by means of special crash tests. In particular types of crash tests, a dummy object is situated inside a moved object, which represents a vehicle. The dummy object then represents the vehicle driver or the passenger of the vehicle. In other types of crash tests, a moved object, which represents a vehicle, strikes onto a dummy object. In this case, the dummy object represents for example a pedestrian or a cyclist who is moving at a usually lower speed compared to the vehicle.
Other approaches for improving road safety are based on so-called driver assistance systems, which are installed in motor vehicles. Such driver assistance systems have suitable sensor systems which are able to detect and identify the spatial environment of the (travelling) motor vehicle. Such driver assistance systems are intended to identify critical traffic situations and to warn the driver of the vehicle, so that accidents can be avoided. Furthermore, driver assistance systems can prevent or at least lessen the consequences of an accident, by activating in a manner adapted to the situation particular components of the vehicle, such as for example brakes, steering or airbags.
From US 2005/0155441 A1 a system is known for the simulation of collisions of a dummy object with a motor vehicle. The dummy object is suspended by means of cables at a rail system and can be moved transversely to the direction of travel of an approaching motor vehicle. The dummy object imitates a human body and comprises a head, a neck, a torso, and arms and legs.
In a reliable testing of the functional capability of driver assistance systems, it should be taken into consideration that the movement behavior for example of pedestrians in road traffic is, however, relatively complex, which in reality makes a detection and an identification of a pedestrian difficult. In this context, a differentiation can be basically made between three basic forms of movement: walking, running, and sprinting.
Walking is the basic form of movement which is to be encountered most frequently in road traffic. Here, one foot is always touching the ground, the respectively other foot is placed in front of the torso, the limbs are approximately extended and the upper body remains substantially straight.
In the running basic form of movement, both feet are briefly without contact with the ground and the step size is greater than when walking. One foot is generally placed directly under the torso, the upper body remains largely straight or is situated in a slightly forward position. The speed can be constant over a lengthy period of time, depending on the physical fitness of the person concerned. Running children, who are initially concealed by an object such as a parking vehicle for example, are encountered very frequently in road traffic.
In the third basic form of movement, sprinting, the speed can only be maintained over a relatively short period of time. Most of the time, both feet have no contact with the ground. A contact with the ground is brought about in that the respective foot is placed onto the ground under the torso with the ball of the foot. In addition, in the sprinting basic form of movement the step size is very large and the upper body shifts distinctly forward.
In active driver assistance systems which warn the vehicle occupants either about dangerous situations or which intervene independently in the driving process, it is necessary to test their functional capability by suitable methods using dummy objects. Test methods and dummy objects are necessary, which reproduce possible traffic situations in a manner as close to reality as possible.
On identifying a pedestrian, the detection process is usually carried out in two stages. In a first stage, the so-called initial detection, it is important that as far as possible all pedestrians in a relevant environmental area of the vehicle are detected. It is accepted here that objects are also detected erroneously as possible pedestrians. In the subsequent second stage, the so-called classification, the detected objects are classified as pedestrians or as non-pedestrians. For the classification, time-dependent features of the detected objects, such as for example leg movements, are used for the classification. If two-dimensional test objects, as are known for example from DE 10 2008 025 539 A1, are used as dummy objects, then for example in the recreation of a simple crossing over by a pedestrian the view angle of the dummy object on an approach of the vehicle can change by up to 60°. Here, a two-dimensional object would pass from a contour describing only the silhouette into approximately a line contour. This would lead to incorrect data in the development and testing of driver assistance systems. It is therefore important to construct dummy objects three-dimensionally and as similarly to humans as possible and to move them in a manner as close to reality as possible. Moreover, it is desired to construct a dummy object to be so robust that it can be used for a multiplicity of crash tests. Only in this way the costs for informative crash tests can be kept low.
There may be a need to provide a dummy object which can be constructed and moved in a manner similar to a human and which has, in addition, a high degree of robustness or respectively stability, so that it can be used non-destructively for a multiplicity of realistic crash tests.